Place 750g (1lb 10oz) gooseberries and 1 large chopped onion in a preserving pan or large saucepan. Add 1 tablespoon ground ginger, 1 teaspoon mustard seeds, ½ teaspoon chilli flakes and a generous pinch of salt.
Pour in 375ml (13floz) white wine vinegar and bring to a gently simmer. Cook the gooseberries gently for 30 minutes until softened and beginning to break down.
Stir in 375g (13oz) light muscovado sugar and cook gently stirring constantly until the sugar dissolves.
Once the sugar has dissolved bring to a rapid boil and cook uncovered for about 30 minutes until the chutney is thick. Stir occasionally to begin with and then frequently as the cooking time goes on to prevent the mixture from burning on the base of the pan.
The chutney is ready when you can draw a spoon through the mixture and it will leave a trail that does not immediately fill up with liquid. Spoon into hot sterilized jars. Cover and seal.
Notes
Cook's TipUse a long-handled spoon and stir carefully as the chutney thickens it tends to spit when you stir itStore in a cool dark place. The chutney should keep unopened for up to a year. Once opened consume within 4 weeks.